Color reaction among gallein, thorium(IV) and lanthanum(III) in the coexistence of amphoteric and nonionic surfactants, and its application to the determination of these ions.

Abstract

Color reaction systems among throium(IV) {Th(IV)}, lanthanum(III) {La(III)} and xanthene derivative such as gallein (gall), in the coexistence of amphoteric and nonionic surfactants were studied, and spectrophotometric determinations of these metal ions (0-50μg of Th(IV) or La(III)/10ml) at 620nm by using gall-Th(IV)-La(III) ternary complex in the coexistence of sodium N-lauroylsarcosine (LS) as an amphoteric surfactant and Brij-35 as a nonionic surfactant were developed. The influences of foreign ions in this proposed method were greatly reduced (to 1/2-1/10) in comparison with the method in the presence of cationic surfactant alone.